My laboratory studies the molecular biology of transformation sensitive gene expression and the regulation of gene expression in senescence. Our present work focuses on the identification of the specific sequence motifs that mediate the tumor promoter and second messenger stimulation of cathepsin L gene transcription. In addition, we are studying the regulation of cathepsin B, cathepsin D, and interleukin-8 gene expression in HL-60 cells treated with various differentiating agents.